In order to measure the AC current passing through a solid bus bar, it is desirable to have a Rogowski-type coil on a printed circuit board that is rigid and may be mounted on the bus bar.
Current efforts to realize a Rogowski coil on a printed circuit board employ multiple coils on multiple printed circuit boards. The coils can be arranged to cancel the effects of outside magnetic fields when the coils are wired in series in electrically opposite directions. This method is similar to a traditional Rogowski coil where passing a single Rogowski coil's conductor back through the coil's helical windings provides outside field rejection and cancellation.
In such Rogowski coils the use of multiple printed circuit boards effectively increases the turns-count of the Rogowski coil, providing the benefit of increased output voltage. However, the use of multiple printed circuit boards also increases the overall cost and complexity. Furthermore, the interconnects required to link the multiple coil printed circuit boards introduce additional failure points in the Rogowski current transducer system reducing reliability.
It would be desirable to have a Rogowski coil realized in a single printed circuit board, that provided both the outside field rejection of a traditional Rogowski coil, and the increased output voltage similar to the multiple printed circuit board Rogowski coil arrangements.